1. Field of the Invention
The present invention generally relates to spoken dialog systems, and more particularly to a method and apparatus for constructing prompts that allow an un-ambiguous presentation of confusable list items to a user.
2. Description of the Related Art
In spoken dialog systems, sometimes there are dialog states where users have to make a selection from a list of items. These lists are often dynamic, obtained as a result of a database query. To present the list choices to the user, a prompt is constructed with these items and is played back to the user by the system. However, if the list items are homophones (acoustically similar) an obvious problem arises for users to distinguish between them and select the correct item.
An example of such a dialog system is a name dialing system that allows users to say the name of the person they wish to call. These systems sometimes have a disambiguation feature. In a disambiguation feature, if for some user utterance the ASR returns more than one hypothesis, all having nearly equal confidence values, the system prompts the caller with these choices and asks them to select one from the list. For example, “did you say Jeff Kuo, Jeff Guo, or Jeff Gao?” Systems that have such disambiguation naturally run into the issue of constructing an un-ambiguous prompt since the list items arise due to their being acoustically confusable.
There is currently no conventional known solution to this problem.